<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>各种合并单元格</title>
  <style>
    td {
      width: 25px;
      text-align: center;
    }
  </style>
</head>
<body>
  <table border="1" style="border-collapse:collapse;">
  	<tr>
  		<td colspan="12">1</td>
  		<td rowspan="12">2</td>
  	</tr>
  	<tr>
  		<td rowspan="12">4</td>
  		<td colspan="10">5</td>
  		<td rowspan="10">6</td>
  	</tr>
  	<tr>
  		<td rowspan="10">8</td>
  		<td colspan="8">9</td>
  		<td rowspan="8">10</td>
  	</tr>
  	<tr>
  		<td rowspan="8">12</td>
  		<td colspan="6">13</td>
  		<td rowspan="6">14</td>
  	</tr>
  	<tr>
  		<td rowspan="6">16</td>
  		<td colspan="4">17</td>
  		<td rowspan="4">18</td>
  	</tr>
  	<tr>
  		<td rowspan="4">20</td>
  		<td colspan="2">21</td>
  		<td rowspan="2">22</td>
  	</tr>
  	<tr>
  		<td rowspan="2">24</td>
  		<td>25</td>
  	</tr>
  	<tr>
  		<td colspan="2">23</td>
  	</tr>
  	<tr>
  		<td colspan="4">19</td>
  	</tr>
  	<tr>
  		<td colspan="6">15</td>
  	</tr>
  	<tr>
  		<td colspan="8">11</td>
  	</tr>
  	<tr>
  		<td colspan="10">7</td>
  	</tr>
  	<tr>
  		<td colspan="12">3</td>
  	</tr>
  </table>
</body>